mediawiki-extensions-Visual.../modules/es/models/es.DocumentModel.js
2011-11-02 21:31:45 +00:00

1169 lines
35 KiB
JavaScript

/**
* Creates an es.DocumentModel object.
*
* es.DocumentModel objects extend the native Array object, so it's contents are directly accessible
* through the typical methods.
*
* @class
* @constructor
* @extends {es.DocumentModelNode}
* @param {Array} data Model data to initialize with, such as data from es.DocumentModel.getData()
* @param {Object} attributes Document attributes
*/
es.DocumentModel = function( data, attributes ) {
// Inheritance
es.DocumentModelNode.call( this, null, data ? data.length : 0 );
// Properties
this.data = es.isArray( data ) ? data : [];
this.attributes = es.isPlainObject( attributes ) ? attributes : {};
// Auto-generate model tree
var nodes = es.DocumentModel.createNodesFromData( this.data );
for ( var i = 0; i < nodes.length; i++ ) {
this.push( nodes[i] );
}
};
/* Static Members */
/**
* Mapping of symbolic names and node model constructors.
*/
es.DocumentModel.nodeModels = {};
/**
* Mapping of symbolic names and nesting rules.
*
* Each rule is an object with a parents and children property. Each of these properties may contain
* one of two possible values:
* Array - List of allowed element types (if empty, no elements will be allowed)
* Null - Any element type is allowed (as long as the other element also allows it)
*
* @example Paragraph rules
* {
* 'parents': null,
* 'children': []
* }
* @example List rules
* {
* 'parents': null,
* 'children': ['listItem']
* }
* @example ListItem rules
* {
* 'parents': ['list'],
* 'children': []
* }
*/
es.DocumentModel.nodeRules = {};
/**
* Mapping of operation types to pure functions.
*
* Each function is called in the context of a state, and takes an operation object as a parameter.
*/
es.DocumentModel.operations = ( function() {
function invalidate( from, to ) {
this.rebuild.push( { 'from': from, 'to': to } );
}
function retain( op ) {
annotate.call( this, this.cursor + op.length );
this.cursor += op.length;
}
function insert( op ) {
if ( es.DocumentModel.isStructuralOffset( this.data, this.cursor ) ) {
// TODO: Support tree updates when inserting between elements
} else {
// Get the node we are about to insert into
var node = this.tree.getNodeFromOffset( this.cursor );
if ( es.DocumentModel.containsElementData( op.data ) ) {
var nodeParent = node.getParent();
if ( !nodeParent ) {
throw 'Missing parent error. Node does not have a parent node.';
}
var offset = this.tree.getOffsetFromNode( node ),
length = node.getElementLength() + op.data.length,
index = nodeParent.indexOf( node );
if ( index === -1 ) {
throw 'Missing child error. Node could not be found in its parent node.';
}
// Remove the node we are about to insert into from the model tree
nodeParent.splice( index, 1 );
// Perform insert on linear data model
es.insertIntoArray( this.data, this.cursor, op.data );
annotate.call( this, this.cursor + op.data.length );
// Regenerate nodes for the data we've affected
var nodes = es.DocumentModel.createNodesFromData(
this.data.slice( offset, length )
);
// Insert new elements into the tree where the old one used to be
for ( var i = nodes.length; i >= 0; i-- ) {
this.tree.splice( index, nodes[i] );
}
} else {
// Perform insert on linear data model
es.insertIntoArray( this.data, this.cursor, op.data );
annotate.call( this, this.cursor + op.data.length );
// Update model tree
node.adjustContentLength( op.data.length );
}
}
this.cursor += op.data.length;
}
function remove( op ) {
var elementLeft = es.DocumentModel.isElementData( this.data, this.cursor ),
elementRight = es.DocumentModel.isElementData( this.cursor + op.data.length );
if ( elementLeft && elementRight ) {
// TODO: Support tree updates when removing whole elements
} else {
if ( es.DocumentModel.containsElementData( op.data ) ) {
// TODO: Support tree updates when removing partial elements
} else {
// Get the node we are removing content from
var node = this.tree.getNodeFromOffset( this.cursor );
// Remove content from linear data model
this.data.splice( this.cursor, op.data.length );
// Update model tree
node.adjustContentLength( -op.data.length );
}
}
}
function attribute( op, invert ) {
var element = this.data[this.cursor];
if ( element.type === undefined ) {
throw 'Invalid element error. Can not set attributes on non-element data.';
}
if ( ( op.method === 'set' && !invert ) || ( op.method === 'clear' && invert ) ) {
// Automatically initialize attributes object
if ( !element.attributes ) {
element.attributes = {};
}
element.attributes[op.key] = op.value;
} else if ( ( op.method === 'clear' && !invert ) || ( op.method === 'set' && invert ) ) {
if ( element.attributes ) {
delete element.attributes[op.key];
}
// Automatically clean up attributes object
var empty = true;
for ( var key in element.attributes ) {
empty = false;
break;
}
if ( empty ) {
delete element.attributes;
}
} else {
throw 'Invalid method error. Can not operate attributes this way: ' + method;
}
}
function annotate( to ) {
var i,
j,
length,
annotation;
// Handle annotations
if ( this.set.length ) {
for ( i = 0, length = this.set.length; i < length; i++ ) {
annotation = this.set[i];
// Auto-build annotation hash
if ( annotation.hash === undefined ) {
annotation.hash = es.DocumentModel.getAnnotationHash( annotation );
}
for ( j = this.cursor; j < to; j++ ) {
// Auto-convert to array
if ( es.isArray( this.data[j] ) ) {
this.data[j].push( annotation );
} else {
this.data[j] = [this.data[j], annotation];
}
}
}
}
if ( this.clear.length ) {
for ( i = 0, length = this.clear.length; i < length; i++ ) {
annotation = this.clear[i];
// Auto-build annotation hash
if ( annotation.hash === undefined ) {
annotation.hash = es.DocumentModel.getAnnotationHash( annotation );
}
for ( j = this.cursor; j < to; j++ ) {
var index = es.DocumentModel.getIndexOfAnnotation( this.data[j], annotation );
if ( index !== -1 ) {
this.data[j].splice( index, 1 );
}
// Auto-convert to string
if ( this.data[j].length === 1 ) {
this.data[j] = this.data[j][0];
}
}
}
}
}
function mark( op, invert ) {
var target;
if ( ( op.method === 'set' && !invert ) || ( op.method === 'clear' && invert ) ) {
target = this.set;
} else if ( ( op.method === 'clear' && !invert ) || ( op.method === 'set' && invert ) ) {
target = this.clear;
} else {
throw 'Invalid method error. Can not operate attributes this way: ' + method;
}
if ( op.bias === 'start' ) {
target.push( op.annotation );
} else if ( op.bias === 'stop' ) {
var index = es.DocumentModel.getIndexOfAnnotation( target, op.annotation );
if ( index === -1 ) {
throw 'Annotation stack error. Annotation is missing.';
}
target.splice( index, 1 );
}
}
return {
// Retain
'retain': {
'commit': retain,
'rollback': retain
},
// Insert
'insert': {
'commit': insert,
'rollback': remove
},
// Remove
'remove': {
'commit': remove,
'rollback': insert
},
// Change element attributes
'attribute': {
'commit': function( op ) {
attribute.call( this, op, false );
},
'rollback': function( op ) {
attribute.call( this, op, true );
}
},
// Change content annotations
'annotate': {
'commit': function( op ) {
mark.call( this, op, false );
},
'rollback': function( op ) {
mark.call( this, op, true );
}
}
};
} )();
/* Static Methods */
/*
* Create child nodes from an array of data.
*
* These child nodes are used for the model tree, which is a space partitioning data structure in
* which each node contains the length of itself (1 for opening, 1 for closing) and the lengths of
* it's child nodes.
*/
es.DocumentModel.createNodesFromData = function( data ) {
var currentNode = new es.DocumentModelNode();
for ( var i = 0, length = data.length; i < length; i++ ) {
if ( data[i].type !== undefined ) {
// It's an element, figure out it's type
var element = data[i],
type = element.type,
open = type[0] !== '/';
// Trim the "/" off the beginning of closing tag types
if ( !open ) {
type = type.substr( 1 );
}
if ( open ) {
// Validate the element type
if ( !( type in es.DocumentModel.nodeModels ) ) {
throw 'Unsuported element error. No class registered for element type: ' + type;
}
// Create a model node for the element
var newNode = new es.DocumentModel.nodeModels[element.type]( element );
// Add the new model node as a child
currentNode.push( newNode );
// Descend into the new model node
currentNode = newNode;
} else {
// Return to the parent node
currentNode = currentNode.getParent();
}
} else {
// It's content, let's start tracking the length
var start = i;
// Move forward to the next object, tracking the length as we go
while ( data[i].type === undefined && i < length ) {
i++;
}
// Now we know how long the current node is
currentNode.setContentLength( i - start );
// The while loop left us 1 element to far
i--;
}
}
return currentNode.getChildren().slice( 0 );
};
/**
* Creates a document model from a plain object.
*
* @static
* @method
* @param {Object} obj Object to create new document model from
* @returns {es.DocumentModel} Document model created from obj
*/
es.DocumentModel.newFromPlainObject = function( obj ) {
if ( obj.type === 'document' ) {
var data = [],
attributes = es.isPlainObject( obj.attributes ) ? es.copyObject( obj.attributes ) : {};
for ( var i = 0; i < obj.children.length; i++ ) {
data = data.concat( es.DocumentModel.flattenPlainObjectElementNode( obj.children[i] ) );
}
return new es.DocumentModel( data, attributes );
}
throw 'Invalid object error. Object is not a valid document object.';
};
/**
* Generates a hash of an annotation object based on it's name and data.
*
* TODO: Add support for deep hashing of array and object properties of annotation data.
*
* @static
* @method
* @param {Object} annotation Annotation object to generate hash for
* @returns {String} Hash of annotation
*/
es.DocumentModel.getAnnotationHash = function( annotation ) {
var hash = '#' + annotation.type;
if ( annotation.data ) {
var keys = [];
for ( var key in annotation.data ) {
keys.push( key + ':' + annotation.data );
}
keys.sort();
hash += '|' + keys.join( '|' );
}
return hash;
};
es.DocumentModel.getIndexOfAnnotation = function( annotations, annotation ) {
if ( annotation === undefined || annotation.type === undefined ) {
throw 'Invalid annotation error. Can not find non-annotation data in character.';
}
if ( es.isArray( annotations ) ) {
// Find the index of a comparable annotation (checking for same value, not reference)
for ( var i = 0; i < annotations.length; i++ ) {
// Skip over character data - used when this is called on a content data item
if ( typeof annotations[i] === 'string' ) {
continue;
}
if ( annotations[i].hash === annotation.hash ) {
return i;
}
}
}
return -1;
};
/**
* Creates an es.ContentModel object from a plain content object.
*
* A plain content object contains plain text and a series of annotations to be applied to ranges of
* the text.
*
* @example
* {
* 'text': '1234',
* 'annotations': [
* // Makes "23" bold
* {
* 'type': 'bold',
* 'range': {
* 'start': 1,
* 'end': 3
* }
* }
* ]
* }
*
* @static
* @method
* @param {Object} obj Plain content object, containing a "text" property and optionally
* an "annotations" property, the latter of which being an array of annotation objects including
* range information
* @returns {Array}
*/
es.DocumentModel.flattenPlainObjectContentNode = function( obj ) {
if ( !es.isPlainObject( obj ) ) {
// Use empty content
return [];
} else {
// Convert string to array of characters
var data = obj.text.split('');
// Render annotations
if ( es.isArray( obj.annotations ) ) {
for ( var i = 0, length = obj.annotations.length; i < length; i++ ) {
var src = obj.annotations[i];
// Build simplified annotation object
var dst = { 'type': src.type };
if ( 'data' in src ) {
dst.data = es.copyObject( src.data );
}
// Add a hash to the annotation for faster comparison
dst.hash = es.DocumentModel.getAnnotationHash( dst );
// Apply annotation to range
if ( src.start < 0 ) {
// TODO: The start can not be lower than 0! Throw error?
// Clamp start value
src.start = 0;
}
if ( src.end > data.length ) {
// TODO: The end can not be higher than the length! Throw error?
// Clamp end value
src.end = data.length;
}
for ( var j = src.start; j < src.end; j++ ) {
// Auto-convert to array
if ( typeof data[j] === 'string' ) {
data[j] = [data[j]];
}
// Append
data[j].push( dst );
}
}
}
return data;
}
};
/**
* Flatten a plain node object into a data array, recursively.
*
* TODO: where do we document this whole structure - aka "WikiDom"?
*
* @static
* @method
* @param {Object} obj Plain node object to flatten
* @returns {Array} Flattened version of obj
*/
es.DocumentModel.flattenPlainObjectElementNode = function( obj ) {
var i,
data = [],
element = { 'type': obj.type };
if ( es.isPlainObject( obj.attributes ) ) {
element.attributes = es.copyObject( obj.attributes );
}
// Open element
data.push( element );
if ( es.isPlainObject( obj.content ) ) {
// Add content
data = data.concat( es.DocumentModel.flattenPlainObjectContentNode( obj.content ) );
} else if ( es.isArray( obj.children ) ) {
// Add children - only do this if there is no content property
for ( i = 0; i < obj.children.length; i++ ) {
// TODO: Figure out if all this concatenating is inefficient. I think it is
data = data.concat( es.DocumentModel.flattenPlainObjectElementNode( obj.children[i] ) );
}
}
// Close element - TODO: Do we need attributes here or not?
data.push( { 'type': '/' + obj.type } );
return data;
};
/**
* Checks if a data at a given offset is content.
*
* @example Content data:
* <paragraph> a b c </paragraph> <list> <listItem> d e f </listItem> </list>
* ^ ^ ^ ^ ^ ^
*
* @static
* @method
* @param {Array} data Data to evaluate offset within
* @param {Integer} offset Offset in data to check
* @returns {Boolean} If data at offset is content
*/
es.DocumentModel.isContentData = function( data, offset ) {
// Shortcut: if there's already content there, we will trust it's supposed to be there
return typeof data[offset] === 'string' || es.isArray( data[offset] );
};
/**
* Checks if a data at a given offset is an element.
*
* @example Element data:
* <paragraph> a b c </paragraph> <list> <listItem> d e f </listItem> </list>
* ^ ^ ^ ^ ^ ^
*
* @static
* @method
* @param {Array} data Data to evaluate offset within
* @param {Integer} offset Offset in data to check
* @returns {Boolean} If data at offset is an element
*/
es.DocumentModel.isElementData = function( data, offset ) {
// TODO: Is there a safer way to check if it's a plain object without sacrificing speed?
return offset >= 0 && offset < data.length && data[offset].type !== undefined;
};
/**
* Checks if an offset within given data is structural.
*
* Structural offsets are those at the beginning, end or surrounded by elements. This differs
* from a location at which an element is present in that elements can be safely inserted at a
* structural location, but not nessecarily where an element is present.
*
* @example Structural offsets:
* <paragraph> a b c </paragraph> <list> <listItem> d e f </listItem> </list>
* ^ ^ ^ ^ ^
*
* @static
* @method
* @param {Array} data Data to evaluate offset within
* @param {Integer} offset Offset to check
* @returns {Boolean} Whether offset is structural or not
*/
es.DocumentModel.isStructuralOffset = function( data, offset ) {
// Edges are always structural
if ( offset === 0 || offset === data.length ) {
return true;
}
// Structual offsets will have elements on each side
if ( data[offset - 1].type !== undefined && data[offset].type !== undefined ) {
return true;
}
return false;
};
/**
* Checks if elements are present within data.
*
* @static
* @method
* @param {Array} data Data to look for elements within
* @returns {Boolean} If elements exist in data
*/
es.DocumentModel.containsElementData = function( data ) {
for ( var i = 0, length = data.length; i < length; i++ ) {
if ( data[i].type !== undefined ) {
return true;
}
}
return false;
};
/* Methods */
/**
* Creates a document view for this model.
*
* @method
* @returns {es.DocumentView}
*/
es.DocumentModel.prototype.createView = function() {
return new es.DocumentView( this );
};
/**
* Gets copy of the document data.
*
* @method
* @param {es.Range} [range] Range of data to get, all data will be given by default
* @param {Boolean} [deep=false] Whether to return a deep copy (WARNING! This may be very slow)
* @returns {Array} Copy of document data
*/
es.DocumentModel.prototype.getData = function( range, deep ) {
var start = 0,
end;
if ( range !== undefined ) {
range.normalize();
start = Math.max( 0, Math.min( this.data.length, range.start ) );
end = Math.max( 0, Math.min( this.data.length, range.end ) );
}
var data = this.data.slice( start, end );
return deep ? es.copyArray( data ) : data;
};
/**
* Gets the element object of a node.
*
* @method
* @param {es.DocumentModelNode} node Node to get element object for
* @returns {Object|null} Element object
*/
es.DocumentModel.prototype.getElementFromNode = function( node ) {
var offset = this.getOffsetFromNode( node );
if ( offset !== false ) {
return this.data[offset];
}
return null;
};
/**
* Gets the content data of a node.
*
* @method
* @param {es.DocumentModelNode} node Node to get content data for
* @returns {Array|null} List of content and elements inside node or null if node is not found
*/
es.DocumentModel.prototype.getContentFromNode = function( node, range ) {
var length = node.getContentLength();
if ( range ) {
range.normalize();
if ( range.start < 0 ) {
throw 'Invalid range error. Range can not start before node start: ' + range.start;
}
if ( range.end > length ) {
throw 'Invalid range error. Range can not end after node end: ' + range.end;
}
} else {
range = {
'start': 0,
'end': length
};
}
var offset = this.getOffsetFromNode( node );
if ( offset !== -1 ) {
offset++;
return this.data.slice( offset + range.start, offset + range.end );
}
return null;
};
/**
* Gets the range of content surrounding a given offset that's covered by a given annotation.
*
* @method
* @param {Integer} offset Offset to begin looking forward and backward from
* @param {Object} annotation Annotation to test for coverage with
* @returns {es.Range|null} Range of content covered by annotation, or null if offset is not covered
*/
es.DocumentModel.prototype.getAnnotationBoundaries = function( offset, annotation ) {
if ( annotation.hash === undefined ) {
annotation.hash = es.DocumentModel.getAnnotationHash( annotation );
}
if ( es.DocumentModel.getIndexOfAnnotation( this.data[offset], annotation ) === -1 ) {
return null;
}
var start = offset,
end = offset,
item;
while ( start > 0 ) {
start--;
if ( es.DocumentModel.getIndexOfAnnotation( this.data[start], annotation ) === -1 ) {
start++;
break;
}
}
while ( end < this.data.length ) {
if ( es.DocumentModel.getIndexOfAnnotation( this.data[end], annotation ) === -1 ) {
break;
}
end++;
}
return new es.Range( start, end );
};
/**
* Gets a list of annotations that a given offset is covered by.
*
* @method
* @param {Integer} offset Offset to get annotations for
* @returns {Object[]} A copy of all annotation objects offset is covered by
*/
es.DocumentModel.prototype.getAnnotationsFromOffset = function( offset ) {
if ( es.isArray( this.data[offset] ) ) {
return es.copyArray( this.data[offset].slice( 1 ) );
}
return [];
};
/**
* Gets the range of content surrounding a given offset that makes up a whole word.
*
* @method
* @param {Integer} offset Offset to begin looking forward and backward from
* @returns {es.Range|null} Range of content making up a whole word or null if offset is not content
*/
es.DocumentModel.prototype.getWordBoundaries = function( offset ) {
if ( es.DocumentModel.isStructuralOffset( this.data, offset ) ) {
return null;
}
var start = offset,
end = offset,
item;
while ( start > 0 ) {
start--;
if ( typeof this.data[start] !== 'string' && !es.isArray( this.data[start] ) ) {
start++;
break;
}
item = typeof this.data[start] === 'string' ? this.data[start] : this.data[start][0];
if ( item.match( /\B/ ) ) {
start++;
break;
}
}
while ( end < this.data.length ) {
if ( typeof this.data[end] !== 'string' && !es.isArray( this.data[end] ) ) {
break;
}
item = typeof this.data[end] === 'string' ? this.data[end] : this.data[end][0];
if ( item.match( /\B/ ) ) {
break;
}
end++;
}
return new es.Range( start, end );
};
/**
* Gets a content offset a given distance forwards or backwards from another.
*
* @method
* @param {Integer} offset Offset to start from
* @param {Integer} distance Number of content offsets to move
* @param {Integer} Offset a given distance from the given offset
*/
es.DocumentModel.prototype.getRelativeContentOffset = function( offset, distance ) {
if ( es.DocumentModel.isStructuralOffset( this.data, offset ) ) {
throw 'Invalid offset error. Can not get relative content offset from non-content offset.';
}
if ( distance === 0 ) {
return offset;
}
var direction = distance > 0 ? 1 : -1,
i = offset + direction,
steps = 0;
distance = Math.abs( distance );
while ( i > 0 && i < this.data.length - 1 ) {
if ( !es.DocumentModel.isStructuralOffset( this.data, i ) ) {
steps++;
offset = i;
if ( distance === steps ) {
return offset;
}
}
i += direction;
}
return offset;
};
/**
* Generates a transaction which inserts data at a given offset.
*
* @method
* @param {Integer} offset
* @param {Array} data
* @returns {es.Transaction}
*/
es.DocumentModel.prototype.prepareInsertion = function( offset, data ) {
/**
* Balances mismatched openings/closings in data
* @return data itself if nothing was changed, or a clone of data with balancing changes made.
* data itself is never touched
*/
function balance( data ) {
var i, stack = [], element, workingData = null;
for ( i = 0; i < data.length; i++ ) {
if ( data[i].type === undefined ) {
// Not an opening or a closing, skip
} else if ( data[i].type.charAt( 0 ) != '/' ) {
// Opening
stack.push( data[i].type );
} else {
// Closing
if ( stack.length === 0 ) {
// The stack is empty, so this is an unopened closing
// Remove it
if ( workingData === null ) {
workingData = data.slice( 0 );
}
workingData.splice( i, 1 );
} else {
element = stack.pop();
if ( element != data[i].type.substr( 1 ) ) {
// Closing doesn't match what's expected
// This means the input is malformed and cannot possibly
// have been a fragment taken from well-formed data
throw 'Input is malformed: expected /' + element + ' but got ' + data[i].type +
' at index ' + i;
}
}
}
}
// Check whether there are any unclosed tags and close them
if ( stack.length > 0 && workingData === null ) {
workingData = data.slice( 0 );
}
while ( stack.length > 0 ) {
element = stack.pop();
workingData.push( { 'type': '/' + element } );
}
// TODO
// Check whether there is any raw unenclosed content and deal with that somehow
return workingData || data;
}
var tx = new es.Transaction(),
insertedData = data, // may be cloned and modified
isStructuralLoc,
wrappingElementType;
if ( offset < 0 || offset > this.data.length ) {
throw 'Offset ' + offset + ' out of bounds [0..' + this.data.length + ']';
}
// Has to be after the bounds check, because isStructuralOffset doesn't like out-of-bounds offsets
isStructuralLoc = es.DocumentModel.isStructuralOffset( this.data, offset );
if ( offset > 0 ) {
tx.pushRetain( offset );
}
if ( es.DocumentModel.containsElementData( insertedData ) ) {
if ( insertedData[0].type !== undefined && insertedData[0].type.charAt( 0 ) != '/' ) {
// insertedData starts with an opening, so this is really intended to insert structure
// Balance it to make it sane, if it's not already
// TODO we need an actual validator and check that the insertion is really valid
insertedData = balance( insertedData );
if ( !isStructuralLoc ) {
// We're inserting structure at a content location,
// so we need to split up the wrapping element
wrappingElementType = this.getNodeFromOffset( offset ).getElementType();
var arr = [ { 'type': '/' + wrappingElementType }, { 'type': wrappingElementType } ];
es.insertIntoArray( arr, 1, insertedData );
insertedData = arr;
}
// else we're inserting structure at a structural location, which is fine
} else {
// insertedData starts with content but contains structure
// TODO balance and validate, will be different for this case
}
} else {
if ( isStructuralLoc ) {
// We're inserting content into a structural location,
// so we need to wrap the inserted content in a paragraph.
insertedData = [ { 'type': 'paragraph' }, { 'type': '/paragraph' } ];
es.insertIntoArray( insertedData, 1, data );
} else {
// Content being inserted in content is fine, do nothing
}
}
tx.pushInsert( insertedData );
if ( offset < this.data.length ) {
tx.pushRetain( this.data.length - offset );
}
return tx;
/*
* // Structural changes
* There are 2 basic types of locations the insertion point can be:
* Structural locations
* |<p>a</p><p>b</p> - Beginning of the document
* <p>a</p>|<p>b</p> - Between elements (like in a document or list)
* <p>a</p><p>b</p>| - End of the document
* Content locations
* <p>|a</p><p>b</p> - Inside an element (like in a paragraph or listItem)
* <p>a|</p><p>b</p> - May also be inside an element but right before/after an
* open/close
*
* if ( Incoming data contains structural elements ) {
// We're assuming the incoming data is balanced, is that OK?
* if ( Insertion point is a structural location ) {
* if ( Incoming data is not a complete structural element ) {
* Incoming data must be balanced
* }
* } else {
* Closing and opening elements for insertion point must be added to incoming data
* }
* } else {
* if ( Insertion point is a structural location ) {
* Incoming data must be balanced //how? Should this even be allowed?
* } else {
* Content being inserted into content is OK, do nothing
* }
* }
*/
};
/**
* Generates a transaction which removes data from a given range.
*
* When removing data inside an element, the data is simply discarded and the node's length is
* adjusted accordingly. When removing data across elements, there are two situations that can cause
* added complexity:
* 1. A range spans between nodes of different levels or types
* 2. A range only partially covers one or two nodes
*
* To resolve these issues in a predictable way the following rules must be obeyed:
* 1. Structural elements are retained unless the range being removed covers the entire element
* 2. Elements can only be merged if they are of the same time and share a common parent
*
* @method
* @param {es.Range} range
* @returns {es.Transaction}
*/
es.DocumentModel.prototype.prepareRemoval = function( range ) {
var doc = this;
//debugger;
/**
* Return true if can merge the remaining contents of the elements after a selection is deleted
* across them. For instance, if a selection is painted across two paragraphs, and then the text
* is deleted, the two paragraphs can become one paragraph. However, if the selection crosses
* into a table, those cannot be merged.
* @param {Number} integer offset
* @param {Number} integer offset
* @return {Boolean}
*/
function canMerge( range ) {
var node1 = doc.getNodeFromOffset( range.start );
var node2 = doc.getNodeFromOffset( range.end - 1 );
// This is the simple rule we are following for now -- same type & same parent = can merge.
// So you can merge adjacent paragraphs, or listitems. And you can't merge a paragraph into
// a table row. There may be other rules we will want in here later, for instance, special
// casing merging a listitem into a paragraph.
// wait, some nodes don't have types? Is this the top document node?
return (
(
( node1 && node2 ) &&
( node1.type !== undefined && node2.type !== undefined ) &&
( node1.type === node2.type )
) &&
( node1.getParent() === node2.getParent() )
);
}
function mergeDelete( range, tx ) {
// yay, content can be removed in one fell swoop
var removed = doc.data.slice( range.start, range.end );
tx.pushRemove( removed );
}
// remove string content only, retain structure
function stripDelete( range, tx ) {
var lastOperation, operationStart;
var ops = [],
op;
//debugger;
// get a list of operations, with 0-based indexes
for (var i = range.start; i < range.end; i++ ) {
var neededOp = doc.data[i].type === undefined ? 'remove' : 'retain';
op = ops[ ops.length - 1 ];
if ( op === undefined || op.type !== neededOp ) {
ops.push( { type: neededOp, start: i, end: i } );
} else {
op.end = i;
}
}
//debugger;
// insert operations as transactions (end must be adjusted)
for (var j = 0; j < ops.length; j++ ) {
op = ops[j];
if ( op.type === 'retain' ) {
// we add one because retain(3,3) really means retain 1 char at pos 3
tx.pushRetain( op.end - op.start + 1 );
} else if ( op.type === 'remove' ) {
// we add one because to remove(3,5) we need to slice(3,6), the ending is last
// subscript removed + 1.
tx.pushRemove( this.data.slice( op.start, op.end + 1 ) );
} else {
console.log( "this is impossible" );
}
}
}
var tx = new es.Transaction();
range.normalize();
// Retain to the start of the range
if ( range.start > 0 ) {
tx.pushRetain( range.start );
}
// choose a deletion strategy; merging nodes together, or stripping content from existing
// structure.
if ( canMerge( range ) ) {
mergeDelete( range, tx );
} else {
stripDelete( range, tx );
}
// Retain up to the end of the document. Why do we do this?
if ( range.end < doc.data.length ) {
tx.pushRetain( doc.data.length - range.end );
}
return tx;
};
/**
* Generates a transaction which annotates content within a given range.
*
* @method
* @returns {es.Transaction}
*/
es.DocumentModel.prototype.prepareContentAnnotation = function( range, method, annotation ) {
var tx = new es.Transaction();
range.normalize();
if ( annotation.hash === undefined ) {
annotation.hash = es.DocumentModel.getAnnotationHash( annotation );
}
var i = range.start,
span = i,
on = this.data[i].type !== undefined;
while ( i < range.end ) {
if ( this.data[i].type !== undefined ) {
// Don't annotate structural elements
if ( on ) {
tx.pushStopAnnotating( method, annotation );
span = 0;
on = false;
}
} else {
var covered = es.DocumentModel.getIndexOfAnnotation( this.data[i], annotation ) !== -1;
if ( covered && method === 'set' || !covered && method === 'clear' ) {
// Don't set/clear annotations on content that's already set/cleared
if ( on ) {
if ( span ) {
tx.pushRetain( span );
}
tx.pushStopAnnotating( method, annotation );
span = 0;
on = false;
}
} else {
// Content
if ( !on ) {
if ( span ) {
tx.pushRetain( span );
}
tx.pushStartAnnotating( method, annotation );
span = 0;
on = true;
}
}
}
span++;
i++;
}
if ( on ) {
if ( span ) {
tx.pushRetain( span );
}
tx.pushStopAnnotating( method, annotation );
}
if ( range.end < this.data.length ) {
tx.pushRetain( this.data.length - range.end );
}
return tx;
};
/**
* Generates a transaction which changes attributes on an element at a given offset.
*
* @method
* @returns {es.Transaction}
*/
es.DocumentModel.prototype.prepareElementAttributeChange = function( offset, method, key, value ) {
var tx = new es.Transaction();
if ( offset ) {
tx.pushRetain( offset );
}
if ( this.data[offset].type === undefined ) {
throw 'Invalid element offset error. Can not set attributes to non-element data.';
}
if ( this.data[offset].type[0] === '/' ) {
throw 'Invalid element offset error. Can not set attributes on closing element.';
}
tx.pushChangeElementAttribute( method, key, value );
if ( offset < this.data.length ) {
tx.pushRetain( this.data.length - offset );
}
return tx;
};
/**
* Applies a transaction to the content data.
*
* @method
* @param {es.Transaction}
*/
es.DocumentModel.prototype.commit = function( transaction ) {
var state = {
'data': this.data,
'tree': this,
'cursor': 0,
'set': [],
'clear': [],
'rebuild': []
},
operations = transaction.getOperations();
for ( var i = 0, length = operations.length; i < length; i++ ) {
var operation = operations[i];
if ( operation.type in es.DocumentModel.operations ) {
es.DocumentModel.operations[operation.type].commit.call( state, operation );
} else {
throw 'Invalid operation error. Operation type is not supported: ' + operation.type;
}
}
// TODO: Synchronize op.tree - insert elements and adjust lengths
};
/**
* Reverses a transaction's effects on the content data.
*
* @method
* @param {es.Transaction}
*/
es.DocumentModel.prototype.rollback = function( transaction ) {
var state = {
'data': this.data,
'tree': this,
'cursor': 0,
'set': [],
'clear': [],
'rebuild': []
},
operations = transaction.getOperations();
for ( var i = 0, length = operations.length; i < length; i++ ) {
var operation = operations[i];
if ( operation.type in es.DocumentModel.operations ) {
es.DocumentModel.operations[operation.type].rollback.call( state, operation );
} else {
throw 'Invalid operation error. Operation type is not supported: ' + operation.type;
}
}
// TODO: Synchronize op.tree - insert elements and adjust lengths
};
/* Inheritance */
es.extendClass( es.DocumentModel, es.DocumentModelNode );